Shrek 2 GBA: green blobs between screens

[RetroEdit]

In the menu transitions between the Books menu and the Chapter selection menu, there are random green blobs that don't appear on real console or mGBA. You can easily reproduce by loading the game, creating a new save slot, and skipping the intro cutscene by pressing 'Start' to get to the Book menu.

I've included a video below. First is SkyEmu 104c287, second is NanoBoyAdvance 49c1403, third is mGBA 6a31777.

https://www.youtube.com/watch?v=61gzNH9H4C0

(see also: corresponding SkyEmu issue)

[fleroviux]

Looks like I unknowingly had already figured out the relevant sprite vertical mosaic edge-case a few months ago. That change was not merged yet because there still is a minor difference in my test between NBA and hardware. However it's unclear if that difference is down to mosaic or something else. It's also nearly perfect otherwise and happens to fix this bug, so I guess that justifies merging it now.